Diffusion-fast color-formers in a silver halide emulsion



United States Patent DIFFUSION-FAST COLOR-FORMERS IN A SILVER HALIDE EMULSION Kurt Wolfson, Newton, N. J., assignor to Anken Chemical and Film Corporation, Newton, N. J., a corporation of New Jersey No Drawing. Application May 2, 1950, Serial No. 159,658

8 Claims. (Cl. 95-6) This invention relates to photographic color-forming compounds containing coupling substances which are fast to diffusion.

The processes for producing photographic color images from a silver halide emulsion containing color forming substances require the latter to possess a number of physical and chemical properties besides the power to form coupling compounds. They must be non-diffusing in order to remain fixed in the colloid emulsion layer. They must have a certain afiinity for water and yet possess a suitable degree of insolubility. They must have a uniform and sufficient color intensity. Because of these several requirements, which vary according to the particular photographic process employed, it has often been difiicult to prepare color-forming compounds which adequately suit these requirements.

Several types of coupling substances have been proposed with the object of making these color formers immobile in the conventional gelatin silver salt layers for single or multilayer films used in color photography. It has been proposed to incorporate into the coupling molecule, long aliphatic chains of at least nine carbon atoms. Another proposal involves the use of sulfoneamide linkages to produce large coupling molecules. Other proposals involve the combining of polymers or polymerizable substances together with the coupler to form large molecules. These methods of producing large coupling molecules require difficult synthesis procedures resulting in poor yields and often insufiiciently pure products. The polymer type of coupling compound has the further disadvantage of non-uniform distribution of the coupling function within the polymer molecules which results in a varying intensity of the dyes obtained in the subsequent developing process.

The present invention makes available a type of coupling compound produced by the step-wise condensation of amino compounds with halogen derivatives of triazine. Trichloro triazine and tribromo triazine are illustrative. By this method color-forming compounds can be prepared which combine the desirable properties of the several amino compounds which condense. The triazine nucleus is particularly suited for this multifunctional type of molecule since it can combine with three substituents in separate condensation stages. By careful control of the reaction temperature in each condensation stage, good yields of the intermediate reaction products can be obtained. Y

Inthe first stage, large size molecules are built up with di-functional amines to prevent diffusion. The water solubility of the compound is adjusted by means of carboXylic and'sulfonic acid groups and their salts. Coupling positions are made available in each molecule to intensify the color obtainable with the compound.

The condensation may be carried out in the first stage with a diamine. Reacting 2 mols of trichloro triazine and 1 mol of an acid substituted aromatic diamine, and maintaining a reaction temperature of 03 C., the following dichloro triazine derivative is obtained:

where R stands for a benzene or naphthalene ring or other aromatic or heterocyclic function, and A stands for a 'carboxylic acid or sulfonic acid substituent on the respective nucleus. A partial list of suitable amine compounds for this first stage includes:

Benzidene disulfonic acid o,o'-Diamisidine-5,5 disulfonic acid 4,4 diamino stilbene-2,2 disulfonic acid 2,2 diamino 6,6 dibenzothiazolyl disulfonic acid where Z is a group of at least six carbon atoms and may also contain a radical which will couple with the oxidation products of a primary aromatic amino color developer to form a colored image. For example, to obtain a yellow dye on development, an amino benzoyl aceto acetate could be used as the amine in the second stage condensation; in order to obtain a magenta dye on development, an amino-phenylmethylpyrazolone could be used; in order to obtain a blue dye on development, an amino naphthol could be used. A partial list of suitable amine compounds for the second stage condensation includes:

p-Amino-benzoyl-acetanilide p-Amino-benzoyl-acetonitrile 3-arnino-l-phenyl-3-methyl-pyrazolone-5-4'-sulfonic acid 4-amino-salicylic acid Z-amino-l-naphthol-6-sulfonic acid 4-amino-4'-phenoxy-1-phenyl-3-methyl-pyrazolone-5-3"- sulfonic acid The third stage condensation may serve to introduce additional coupling functions into the molecule and thus increase the dye intensity of the resulting product in the development process. The coupling function could be the same as the one introduced in the second stage con-- densation, or. it could be a different coupling function. Preferably, however, the third stage condensation is used to introduce 2 mols of a substituted amine of at least six phenyl is added to the product of the second stage, and carbon atoms (and preferably ten to twelve, to give better the mixture is boiled for one hour. After cooling, the substantive properties) by reaction at reflux temperature reaction mixture is extracted with ether, and the product with one mol of compound type II to give is salted out of the aqueous portion by the addition of III N N 5 sodium chloride. The precipitated compound is filtered by suction. It is then dissolved in 500 cc. of distilled LL A A water and dialyzed through an acetylcellulose membrane, until all by-products are removed. The solution is then G C concentrated on a steam-bath and the sodium salt is prei l cipitated by the addition of alcohol. A yellowish powder 1 results which is easily soluble in water and upon incorpo- Z Z ration into an emulsion and developing with the known where Y is a group which will couple with the oxidation color developing agents gives a brilliant yellow azoproducts of a primary aromatic amino color developer to methine dye image.

form a colored image and may also contain a radical of at least six carbon atoms. A partial list of suitable amine compounds for this third stage condensation includes: Example his (4'6, amino-4 gulf he"),

methylpyrozolone-S -6-dicyclohexylamino-5-triazine-2 4-amino-biphenyl yl-amino) 2,2 dimeth0xybenzidene-5,5' disulfonic acid 2-amino-bispyridyl Dicyclohexylamine The structural formula is as follows:

S0311 son: $04K $03K 0 I /N l I /N 0 H2 n -HNC \OHN NHC \C-NIE[ n CC\ LI 1 H l /OCH1 a l t= t i CH CH 3 /e ia fiE H10 CH: H20 (3111 E20 (3H1 H2? CH2 H1O /irH= H2C\ /CH2 H= J\ /CH2 HzC\ t JHi 0 C 0 0 H2 H2 H2 H2 First stage condensation- A mol of 0,0'-dianisidine The followmg examples Illustrate thls mventlon' 5,5 disulfonic acid is neutralized with sodium carbonate Example I 4,4, bis(Laminmbenzoylacetanilido) 6 (4 to the neutral sodium salt and brought to a volume of bisphenylamino)-s-triazine-2-yl-amin0 stilbene-2,2 di- 9 F- Wlth Water P P 1s cooled to a 'sulfom-c acid to it is added slowly, with stirring, a pre-cooled solution of mol trichloro-triazine in acetone. The reaction The structural formula i as follows; 40 temperature is held between 0 and 3 C. After 30 g N N\ t) I *C E G- G 0:0 l\|T\ /N so H so H IE 0 CH3 0 3 a o 1 I OH: NH NH First stage condensation.- mol of 4,4 diaminominutes more at room temperature, the reaction is comstilbene-2,2' disulfonic acid is neutralized with aqueous plete. sodium carbonate to form the neutral sodium salt and Se nd stage c0ndensati0n. ,i mol of 3'-amino-1 the solution is brought to a volume of 500 cc. with water. henyl-3-methyl-pyrazo1one-5-4-sulfonic acid is neutral- TQ this solution /10 11101 of tl'ichlofo-triaZifle dissolved in ized with sodium carbonate in water and the solution is acetone is added dropwise with stirring and cooling S0 added in several portions to the reaction mixture obtained that the reaction temperature never exceeds 3 C. during in the first stage, each addition being followed by a porthe addition. The resulting suspension is held at room tion of sodium bicarbonate approximately equivalent to temperature for 15 minutesthe hydrochloric acid liberated by the reaction. The Second smge c0ndensati0n.An alcoholic solution of reaction temperature is held at 40 C. and after 4 hours 7 mol of p-amino-benzoyl-acetanilide is added over a at this temperature, the reaction is complete. period of one hour to the reaction mixture obtained in Third stage condensation- A mol of dicyclohcxylthe first stage. The hydrochloric acid developed by the amine is added to the product of the second stage and reaction is neutralized by adding sodium bicarbonate in the mixture boiled for 2 hours. The final product is resmall portions. The temperature is maintained at 40 C. covered and purified as described in Example I. It is a and after 4 hours at this temperature the condensation tan powder which is easily soluble in water and which is complete. gives a magenta color when used as a coupling compound Third stage condensation.-% mol of 4-amino-biin an emulsion.

2,718,466 6 Example lIl.-4,4' bis (4-(4-amin0-2-hydr0xy-1-carboxydrochloric acid formed during the reaction. The final phenyl)-6-dicycl0hexylamin0 5 triazine-Z-yl-amino) product is recovered and purified as described in Examstilbene 2,2- disalfonic acid ple I. It is a tan colored powder which gives a brilliant The Structural formula is as follows: magenta dye image of good strength on development.

on 1 on N N I HOOC-C HNCII (IJHN orr=on NH(|) (l -NH--CO0H bi 0 H I 0 H k F/ 1 i I ex 2% ax 2% H2O CH2 H2O CH2 H (311: Hi? (3H2 H26 /(bH2 H23\ H2 H2\ /CH2 HzC\ CH: C G O C/ H: Hz H2 E: First stage condensation-Same as in Example I. 20 Example V.4,4 bis (5 amino 1 carboxy phenyl Second stage condensatiom i mol of 4-aminosalicylic 2 azo 4' (1 phenyl 3 methyl pyrazolone 5) acid is neutralized with sodium carbonate in water and 6 (4 amino 2 hydroxy 1 carboxy phenyl) the solution is added to the reaction mixture obtained in triazine 2 yl amino) stilbene 2,2 disulfonic acid the first stage as described in Example II.

Third stage condensation.--Same as Example 11. The The structural formula 18 as follows:

COOH COOH OC--HGN=N N-N-HC-CO '4 HNC CHN oH=oH -NH-o C-HN Hi i I i N A N 0:11 0:11 CH;

0 t V l IH NE OH OH OOH JJOOH final product is a light brown powder which gives a blue- First stage condensation.-Same as Example I. green dye upon color development. Second stage cOndensatiOm- A mol of the sodium salt of 5-amin0-benz0ic acid-2-azo-4-(1-phenyl-3'- methyl-pyrazolone-S) in aqueous solution is added to the reaction mixture obtained in the first stage as described in Example II.

Third stage condensatiom i mol of the sodium salt Example IV.4,4 bis (4,6 bis (4"-amino-4-phen0xy-1 phenyl 3'- methyl pyrazolone 5 3" sulfonic acid) triazine 2 yl amino) stilbene 2,2 disulfonic acid The structural formula is as follows: of 4-aminosalicylic acid is added to the product obtained /N\ /N\ /OCCH1 0 o o i N N N N=C N/ \00 03H \G% dOaH OaH \C/ v 03H H: NH 1 in v(311a SOQH SQzH lfil 00 N (10 CHaC-(BH:; CHs- -'CH2 First stage condensatiomAame as Example I. in the second stage. The mixture is boiled for 2 hours Second and third stage condensation.-% mol of 4"- and sodium bicarbonate added to neutralize the liberated amino 4' phenoxy 1 phenyl 3 methyl py acid. The product is recovered and purified as derazolone 5 3" sulfonic acid is neutralized with scribed in Example I. It is an intense yellow, water sodium carbonate and the neutral sodium salt in aqueous soluble powder containing two difierent coupling centers solution is added to the product of the first stage. The in each molecule, and it produces a yellow color on demixture is boiled for 2 hours during which time mol velopment. of sodium bicarbonate is added to neutralize the hy- As many different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments described herein except as defined by the appended claims.

I claim:

1. A silver halide emulsion for color photography containing a color forming Component having the general formula:

in which R stands for aryl, A stands for an acid group selected from the class consisting of carboxylic acids, sulfonic acids and'their salts, Y stands for a group which will couple with the oxidation products of a primary aromatic amino color developer to form a colored image and may also contain a radical of at least six carbon atoms, and Z stands for a group of at least six carbon atoms and may also contain a radical which will couple with the oxidation products of a primary aromatic amino color developer to form a colored image.

2. A silver halide emulsion for color photography containing a color forming component having the general formula:

in which R stands for aryl, A stands for an acid group selected from the class consisting of carboxylic acids, sulfonic acids, and their salts, and Z is a radical of at least ,six carbon atoms which also contains a. radical capable of coupling with the oxidation products of a primary aromatic amino developer to form a colored image.

3. A silver halide emulsion for color photography containinga color-forming component having the general formula:

in which R stands for aryl, A stands for an acid group selected from the class consisting of carboxylic acids, sulfonic acids and their salts, Z is a radical of at least six carbon atoms which also contains a radical capable of coupling with the oxidation products of a primary aromatic amino developer to form a colored image, and Z is a group which will couple with the oxidation products of a primary aromatic amino color developer to form a colored image and may also contain a radical of at least six carbon atoms.

4. A silver halide emulsion for color photography containing a color-forming component consisting of: 4,4-bis- (4 amino benzoylacetanilido) 6 (4 bisphenylamino) .s triazine 2 yl aminostilbene 2,2 disulfonic acid.

5. A silver halide emulsion for color photography containing a color-forming component consisting of: 4,4 bis- (4 (3 amino sulfo 1 phenyl 3 methylpyrazolone 5) 6 dicyclohexylamino 5 triazine 2- yl amino)2,2 dimethoxybenzidine 5,5 disulfonic acid.

6. A silver halide emulsion for color photography containing a color-forming componfint consiSfing of: 4,4 bis- (4 (4 amino 2 hydroxy 1 carboxyphenyl) 6- dicyclohexylamino 5 triazine 2 yl amino) stilbene- 2,2 disulfonic acid.

7. A silver halide emulsion for color photography containing a color-forming component consisting'of: 4,4 bis (4,6 bis (4" amino 4 phenoxy 1 phenyl 3 methylpyrazolone 5 3" sulfonic acid) triazine 2 ylamino) stilbene 2,2 disulfonic acid.

8. A silver halide emulsion for color photography containing a color-forming component consisting of: 4,4 bis (5 amino 1 carboxyphenyl 2 azo 4(1 phenyl 3- methyl-pyrazolone 5) 6 (4 amino 2 hydroxy 1- carboxyphenyl) triazine 2 yl amino) stilbene 2,2- disulfonic acid.

References Cited in the file of this patent UNITED STATES PATENTS 1,625,533 Fritzche et a1 Apr. 19, 1927 2,179,239 Wilmanns et al Nov. 7, 1939 2,306,410 Schinzel Dec. 29, 1 942 2,306,439 Hentrich Dec. 29, 1942 2,394,527 Woodward Feb. 5, 1946 2,418,747 Bavley Apr. 8, 1947 2,473,475 Keller June 14, 1949 

1. A SILVER HALIDE EMULSION FOR COLOR PHOTOGRAPHY CONTAINING A COLOR FORMING COMPONENT HAVING THE GENERAL FORMULA: 